1. Slice the King's Hawaiian rolls in half. Line the bottom of two 9X11 baking pans with the bottom halves of the rolls, 24 in each pan (they should just fit). Spread the ham over the rolls, and then layer the Swiss cheese on top. Place the other halves of the rolls on top. Set aside.
2. In a small sauce pan, combine the butter, mustard, Worcestershire sauce, and dried onions. Over medium heat, stir until the butter has melted to create the sauce. Pour equal parts of the sauce over top of the rolls, and then sprinkle the tops with the poppy seeds. Cover the pans tightly!
When You're Ready to Bake:
Preheat the oven to 350°F. Place the covered baking dishes in the oven for 20 minutes. Uncover and bake for an additional 5 minutes, or until the cheese has finished melting. Serve warm or at room temperature. Makes 48 mini sandwiches.